System of distribution.



R. B. WILLIAMSON.

` SYSTEM 0F DISTRIBUTION.

APPLICATION man senso. 1909.

Patente May 4, 1915.

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I u gaa/....55 c@ En STATpgpafr-ENT oFiuoE.

ROBERT B. WILLAMSON,`OF MILWAUKEE, WISCONSIN, ASSIGNOR, BY MESNEASSIGN- MENTS, TO ALLIS-CHAL1IERS MANUFACTURING COMPANY, A COR-PORAT-TGN' 0F DELAWARE.

SYSTEM OF, DISTRIBUTION.

Specification of Letters Patent.

Applica-th vfiled September 30, 1909. Serial No. 520,330.

To all wlw/n fit may conoci-a Be it known that I., Rohner B. YVILLIAM- SON, a citizenof the United States, residing at Milwaukee, in the county of Milwaukee and State of Wisconsin have invented cen tain new and useful liniirovements in Systems of Distribution, of which the following is a full, clear, aiid'eXact speciiication.

`My invention relates to systems of electrical distribution.

.In many electrical systems, there are wide load fluctuations which occur with considerable rapidity. 1f these fluctuations in their entirety fall upon the generator or generators, the latter must generally be of sufficient capacity to carry the greatest load. Since this greatest load is often several times large as the average load, the generator or generators supplying the system, together with their driving apparatus, must be considerably larger than is economical tor that average load. Moreover, the sudden li'uctuations in the demand on the generators and' their driving apparatus tend to produce various troubles in operation.

It is the object of my presentlinvention to provide a system in which the load on the generator orgenerators supplying the systein may be maintained substantially'V constantregardless of fluctuations in the load on the system.l This allows the capacity of the generator or generators and their driving apparatus to be very much reduced ,e-reduced, indeed, so that it is necessary only thattheir capacity exceed very slightly that necessary for the average load.

In carrying out my invention, a freely running dynamo-electric machine on whose shaft is a ily wheel is connected across the f 'circuit on which is the fluctuating load, and

the 'field of this machine is controlled by means responsive to the current supplied byI the generator to the circuit. V

The various novel features of my invention will appear from the description and drawings, and will be particularly pointed out in the claims. l f

Figure 1 of the drawings shows diagram- 'matically afsystem embodying my invention.,

said system showing the reely running dynamoelectrlc machine iieldresistance as I being controlled by yseparately actuated solenoid switches.; Fig. 2 is a diagrammatic View disclosing a niodiiication of my invention,

wherein the compressioie resistanccvof the freely ruiming dynamo-electric machine lield is controlled by a solenoid inthe supply circuit; and, Fig. 3 is another modification ot .my in`ventionwherein the compressible resistance in the freely ruiming dynamoelectric machine lield circuit iscontrolled by a series of solenoid-operated switches.

Patented May a, i915.

A generator 10 supplies a circuit 11k12`, I

. across which is a iluctuating load repre- .sented by a motor 13. This load, for instance, may be the motor or motors which .are used to drivethe rolls of rolling mills. rl`he generator 10 may be excited and regulated in any desired manner, preferably to give a constant electro-motive force. The

load 13' may be controlled in any desired manner in order to obtain sults.

A dynamo-electric machine 14 has its armature connected across the circuit 1112,

the required reand on the shalt of this machine is aiiymachine may wheel 15. The field 16 of this be excited in any desired manner, being here shown as coniiectedacross the circuit 1l-12. The field strength oi' the machine 14 is so varied that the machine acts as a motor to e store energy in the `fly-wheel 15 when the load 13 on the circuit 11h12 is light, but acts as a generator driven by the ily wheel .15 when the load 13 on the circuit 11-12 is heavy. The control of the field of the machine 14 may be obtained in a number' of ways.

In vthe arrangement shown in Fig. 1, av

number of resistance sections 17, 18, '19,' 20 are in the circuit of the field winding 16 of the machine 14. Normally open switches 2l,

22, 23, 24, when closed, short-circuit the respective resistance sections 17, 18, 19, 20. These switches are respectively.operated by solenoids 25, 26, 27, 28, which carry the Whole plied by the generator 10;v These solenoids are soarranged, as by having diiierent numbers of turns or different air gaps, that they respond to different strengths of current.

When'the load 13 onthe circuit 11-12 isv light, the dynanio-electric machine 111 runs as a motor to store energy in the fly-wheel 15. When the load 13 on theA circuit 11,12 increases, the current supplied by the generator 10 also increases somewhat and the solenoid. 25 closes its switch 21 to shortj or a 'proportional-part of the current supict circuit the resistance section17. This increases thelicld strength and therefore the electro-motive force ofV the machine 14, and

causes it to take less current as a motor or to act as a generator driven by the now slack# .cning fly-Wheel 15 to supply current to the circuit 11*12 and help furnish the current necessary for the load 13. if the cutting out of the resistance section 17 is not sul'licient to keep the load on the generator 10 practically 'at its normal predetermined Value, vthe solenoid 26 raises its switch 22 to cut out the resistance section 18, which further increases the field strength and electro-motive force of the machine 14 and causes it to take still less current as a motor or to supply still more current as a generator. 1f necessary to keep the current supplied by the generator 10 at substantially its normal value, the solenoids 27 and 28 also lift their switches 23A and 24 in turn to cut out the resistance sections l19 and 20 and to increase still further the eld strength of the machine 14.,

When the load 13 now decreases, the solenoids 28, 27, 26, 25, or such of them as have raised their respective switches, drop such switches in turn to cut intoy circuit such oi' the resistance sections 17, 18, 19, and 20 as had been cut out of circuit. This diminishes the field strength of the machine 14 and causes it vto supply less current as a/gencra-- takes such excess and stores up energy in the ily-wheel 15. vlf'l/lienever there is any excess of current demanded by the load 12? over that supplied by the generator l0, the ily-wheel l5 gives up its stored energynnd drives the machine 14 as a generator' to supply such excess. This system keeps the load on the generatori() substantially constant within very small limits, in spite vot' wide fluctuations in lhc load 13. 'lhcse limits may be made as small as desired by properly proportioning and adjusting the several solenoid switches.

ln the arrangement shown in Fig. 2, a carbon pile resistance 29 is in circuit with the field winding 11i. A solenoid 30 carrying current supplied by the generator 1() or a current proportional thereto tends to iuerease the. pressure `on the' ycarbon pile against the action of a spring 31. As the load 13 on the circuitl 11--12 increases, a small part of the increase of current flows through the solenoid 30'and causes itto'` diminish the resistance el the carbon pile ymachine 14.

rent in the armature makes the greater part of the increase in'current demanded by the load 13. As the-load 13 decreases', the`- solenoid 30 diminishes its pressure on the carbon pile 29, and the resultant change' inthe strength ol" the field 16 causes the machine' motor to maintain the load on the generator 10 substantially constant.

In the arrangementshown in-Fig. 3, a carbon pile 4resistance 32 is in circuit with .14 to act less as a generator or more. as a i the field winding 16. This carbon pile re- 13 on the circuit 11--12 increases,.there is a very small rise in the current supplied by the generator 10. According to the extent f of this rise, some or all of the solenoids 38,

39, 40, and 41 raise their associated switches 34, 35, 36, 37 to cut into circuit sections of the solenoid As cach section of this sole- -noid is cut into circuit it increases the pull ot' the solenoid against the spring 42, and vthus increases the pressure on the carbon pile 32, the strength of thecurrent in the field winding 16, and the electr-emotive force generated bythe machine 14. This causes such machine to take less .current as a motor or to supply more current as a generator to maintain substantially constant the current supplied by the generator 10. As the load 13 decreases, the solenoids 41, 40, 39, and 38, or such of them as have opened their associated switches, drop their switches in turn to decrease the pull of the solenoid 33 and the electromotive force generated by the This variation in the electromotive vforce ol the machine 14 is so proportioned that the current supplied by the generator 10 varies but very slightly Jfrom a predetermined value, the machine 14 acting as a generator or as a motor as required to absorb tbc fiuctuations in current.

Various adjustments of the several `parts may he provided. For instance, the springs 31 and 42 may be adjustable. The proportion between the currents in the solenoids 25, 26, 27, 28, 30, 38, 39, 4G, and 41 and that delivered by the generator- 10 may be varied,

- s by rheostats 43. The strength of the sole-l noid 33 may be varied, as by a rheostat 44 in circuit therewith. A switch 45, with which may he associated a discharge resistance 46 for taking'the lield discharge of the motor 14, may be provided for the circuit of the field winding 16, and there may be a manually operated rhcostat 47 in such circuit. A starting resistance 48 may be provided in the armature circuit of the .ma-l' chine 14.

p scribed, and all such which do not involve a claims.

departure from the spirit and 'scope of my invention Iaim to cover in the following y What l claim as new is:

l. In combination,4 a generator, a circuit supplied thereby, a dynamo-electric machine connected across said circuit, a iy-Wheel on the shaft ofl said machine, a compressible resistance in the field circuit of said machine, and a plurality of solenoid operated switches directly responsive to different strengths ofcurrent supplied b said generator and operating to vary t e pressure on sai compressible resistance changing the effective resistance thereof for causlngiuctuations in the load on said supplied circuit to be absorbedby said machine and4 iiy- Wheel.

2. In combination, a generator, a circuit supplied thereby, a' dynamo-electric machine, means for regulating 'the voltage of said machine comprising a compressible resistance for the machine field circuit,V a series of solenoids responsive to different strengths of current supplied by said generator, a separate solenoid the core of Whichis actuated to change the pressure on said compressible resistance medium, and switches operated by said series of solenoids and being adapted to vary the number of effective turns of said separate solenoid for controlling the amount of effective resistance in said field circuit.

3. In combination With an electric circuit, a resistance, means for regulatingv said resistance 'comprising a series of solenoids responsive to different strengths of current in said circuit, switches operated by said sole-n noids, a separate solenoid the core of which is actuated to vary said resistance, said switches when actuated by different strengths of current in said'circutacting to vary the number of effective turns of said separate yto different strengths offcurrent in said cirv cuit,jand an electromagnet the movable part of which is actuatable to vary the Value of said resistance7 said switches being actuatable by different strengths of current in said circuit to vary the effective ampere turns of said electromagnet for controlling the action of said movable part.

In testimony whereof I affix my signature, in the presence of two witnesses. I

ROBERT B. WILLIAMSON.

Witnesses: G. B. SCHLEY, CHAs.'L. BYRON.

445 solenoid'forv controlling the' yvalue of said l miV 

